The conventional eye drop container is a small, cylindrical bottle having nozzle. Eye drops are dispensed into the eye by positioning the bottle in a mostly inverted position over the eye, and gently compressing the bottle in order to force medicative solution through the nozzle and into the eye. This procedure requires the user to first tilt his or her head back into a substantially horizontal position. The user must then retract one or both eyelids from the eye with one hand, while dispensing eye drops with the other.
For most people, the procedure for dispensing eye drops is difficult and imprecise. With the conventional dispenser, the user attempts to drop medicament directly onto the surface of the eyeball. This produces unwanted blinking and natural tear flow due to the particular sensitivity of the conjunctiva. This, in turn, limits the time in which the medicament remains effective.
The preferred area of the eye for dispensing is the lower eyelid, or conjunctival sac. Yet, the use of a conventional eye drop container makes it difficult to align the nozzle with the conjunctival sac.
An additional obstacle to the proper dispensing of eye drops is the risk of contamination to the medicament. With the conventional eye drop dispenser, the user is required to place the fingers of one hand in close proximity to the eye so as to retract the upper and/or lower eyelids from the surface of the eyeball. This creates a risk of contamination of the medicament, as well as infection of the eye.
Further, it is well known that any detachable parts of the dispenser, such as the cap, must be set aside during the application process. The cap then becomes a source of contamination when it comes into contact with dirt or other particles from the surfaces upon which it rests. The contaminant is transmitted to the dispensing device when the cap is reinstated over the nozzle.
The patent literature presents various examples of proposed solutions to overcome the difficulties described above. Typical of the art are those devices disclosed in the following U.S. Patents:
______________________________________ U.S. Pat. No. Inventor(s) Issue Date ______________________________________ 5,007,905 Bauer April 1991 5,030,214 Spector July 1991 5,064,420 Clarke, et al. November 1991 5,133,702 Py July 1992 5,267,986 Py December 1993 5,366,448 Basilice, et al. November 1994 5,387,202 Baron February 1995 5,578,019 Feldman November 1996 5,578,020 Mosley November 1996 5,611,788 Marchment March 1997 5,665,079 Stahl September 1997 ______________________________________
Most of the above referenced patents (U.S. Pat. Nos. 5,007,905, 5,030,214, 5,064,420, 5,133,702, 5,264,986, 5,366,448, 5,387,202, 5,578,019, 5,611,788, and 5,665,079) disclose various eye drop dispensers which utilize a fixed eyelid retractor. These fixed retractors are mounted onto an existing bottle, and cannot be adjusted to properly fit the shape of the user's ocular region.
Another drawback to many of the above referenced patents (U.S. Pat. Nos. 5,064,420, 5,007,905, 5,133,702, and 5,366,448, 5,378,202, 5,578,020, and 5,611,788) is that the dispensing device requires virtually a 90-degree angle between the vertical axis of the bottle and the surface of the conjunctiva. This means that the liquid medicament is applied to the patient in a manner which is uncomfortable and imprecise.
Many of the dispensing devices available actually encompass the eye drop bottle itself These operate purely by tactile, rather than visual, feedback. See, e.g., U.S. Pat. Nos. 5,267,986, 5,387,202, and 5,030,214 and 5,578,020. With these devices, neither the user nor one assisting the user can visually monitor the progress of the liquid as it is dispensed from the bottle.
Finally, a drawback to prior art is that the cap and, perhaps, the dispenser itself, is detachable. This presents a risk of contamination. U.S. Pat. No. 5,578,019 seeks to eliminate this problem by providing a pivoting cap over the nozzle to the eye drop bottle. Rotation of the cap to and away from the axis of the container serves to open and close the bottle. However, the internal surface of the pivoting closure assembly cannot be accessed for cleaning in the event it becomes dirty while in its open state. Moreover, the use of a pivoting closure assembly increases the cost of manufacture and complexity of use.
It is an object of the present invention to provide an eye drop applicator which allows for the dispensing of liquid ocular medication in such a manner that the user need not place his or her fingers near the surface of the eye.
It is also an object of the present invention to provide for an eye drop applicator whose use does not necessitate tilting of the head by the user at an uncomfortable or inconvenient angle.
It is an additional object of the present invention to provide a simple eye drop dispenser which is easy to use, i.e., which can be used with one hand while accurately instilling drops in the conjunctiva, and in such a manner that the user can visually monitor the progress of the liquid as dispensed from the bottle.
It is further an object of the invention to provide a single eye drop dispenser capable of exposing the conjunctival sac of the user regardless of the shape or configuration of their face.
Another object of the invention is to provide an eye drop dispenser having an adjustable guiding arm which secures to any conventional eye drop container, thereby creating an inexpensive means for improving eye drop containers currently available.
Finally, it is an object of the present invention to provide an eye drop dispenser which can be easily cleaned and sealed so as to facilitate sterility.